Dwarf Fortress Bug Tracker - Dwarf Fortress
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IDProjectCategoryView StatusDate SubmittedLast Update
0004493Dwarf FortressWorld Generation -- Generalpublic2011-04-11 01:252012-02-26 21:27
ReporterKhym Chanur 
Assigned ToToady One 
PrioritynormalSeverityminorReproducibilityalways
StatusresolvedResolutionfixed 
Platformx86 (AMD Athlon 7550 Dual-Core)OSMandriva OneOS Version2010 (2.6.33.7)
Product Version0.31.25 
Target VersionFixed in Version0.34.01 
Summary0004493: Turtles only appear in island worlds
DescriptionIf you generate a "[SIZE] REGION" world, then turtles won't be available on embark, and fishing in surface murky pools will always give "The is nothing to catch in the [region] swamps". But if you generate a "[ISLAND] REGION" world, turtles are always available on embark, and you can always catch turtles from murky pools.
Steps To Reproduce
Additional Information
Tagsfishing, turtle, worldgen
Relationships
related to 0004500new  Tropical Lakes always empty; Murky Ponds odd 
Attached Files
Issue History
Date ModifiedUsernameFieldChange
2011-04-11 01:25Khym ChanurNew Issue
2011-04-11 01:27Khym ChanurTag Attached: fishing
2011-04-11 01:27Khym ChanurTag Attached: turtle
2011-04-11 01:27Khym ChanurTag Attached: worldgen
2011-04-12 00:12Khym ChanurNote Added: 0017311
2011-04-12 11:48Granite26Note Added: 0017318
2011-04-12 17:37RossMNote Added: 0017327
2011-04-12 20:19Khym ChanurNote Added: 0017330
2011-04-12 21:15QuietustNote Added: 0017331
2011-04-12 21:16QuietustNote Edited: 0017331bug_revision_view_page.php?bugnote_id=0017331#r6444
2012-02-17 07:49FootkerchiefNote Added: 0019925
2012-02-17 07:50FootkerchiefTag Attached: AWAITING UPDATE
2012-02-17 07:50FootkerchiefRelationship addedrelated to 0004500
2012-02-26 19:55Khym ChanurNote Added: 0020781
2012-02-26 21:26FootkerchiefNote Added: 0020784
2012-02-26 21:26FootkerchiefStatusnew => resolved
2012-02-26 21:26FootkerchiefFixed in Version => 0.34.01
2012-02-26 21:26FootkerchiefResolutionopen => fixed
2012-02-26 21:26FootkerchiefAssigned To => Toady One
2012-02-26 21:27FootkerchiefTag Detached: AWAITING UPDATE

Notes
(0017311)
Khym Chanur   
2011-04-12 00:12   
After doing some more testing:

1) Island worlds don't always give you turtles, and non-islands worlds aren't always bereft of them.

2) Checking the animals populations via "export map/gen info" from Legends mode shows that turtles are actually always present in non-islands worlds, but on average there's less of them than in island worlds. The more turtles there are in the world-wide population, the more likely they're available from export from parent civs, and the more likely you'll be able to fish them out from murky pools.

3) Non-island worlds with large non-frozen oceans have more turtles than ones with small or non-existent oceans.

From all this I'm guessing that the ocean turtle population makes it easier to find turtles in murky pools, and that turtle populations are much denser in oceans then on land with murky pools.
(0017318)
Granite26   
2011-04-12 11:48   
I believe that this is intended behavior. Animals at a site are drawn from world populations.

May be a 'turtles are too rare in murky pools' issue though.
(0017327)
RossM   
2011-04-12 17:37   
Could this have to do with animals being placed in contiguous biomes? Maybe a non-island world can have multiple oceans but only have turtles in one of them.
(0017330)
Khym Chanur   
2011-04-12 20:19   
After doing yet more testing, I've found two things that are contributing to the problem:

1) [BIOME:ANY_POOL] seems to be broken. If I replace the turtle's single [BIOME:ANY_POOL] with six biome tags, one for each

* POOL_TEMPERATE_FRESHWATER
* POOL_TEMPERATE_BRACKISHWATER
* POOL_TEMPERATE_SALTWATER
* POOL_TROPICAL_FRESHWATER
* POOL_TROPICAL_BRACKISHWATER
* POOL_TROPICAL_SALTWATER

then the average number of turtles found in non-island worlds increases, and becomes approximately the same as the number of turtles found in non-island worlds. So I'm guessing that ANY_POOL selects only saltwater during worldgen, but includes freshwater murky pools after embark.

2) A creature with many different biomes has a global population than less than what you should get from the sum off each of the biomes. I tried modding turtles so there'd be three different species, one each for fresh, brackish and salt water. When generating worlds with this mod, the average sum of the populations of all three species was about 2 to 2.5 times larger than the average population for the single turtle species which spanned all three types of water.

Or maybe 0000001 and 0000002 are the same bug, and during world gen only one biome is picked for the species to grow in.
(0017331)
Quietust   
2011-04-12 21:15   
(edited on: 2011-04-12 21:16)
BIOME:ANY_POOL definitely isn't broken - I've looked at a disassembly of the biome token parsing code (because I like to document the behavior of certain tokens on the wiki for modders), and ANY_POOL simply specifies biomes 30-35, which happen to be the 6 POOL biomes you've listed (in that exact order, no less).
(0019925)
Footkerchief   
2012-02-17 07:49   
Reminder sent to: Khym Chanur

Is this bug still present in 0.34.01?
(0020781)
Khym Chanur   
2012-02-26 19:55   
The problem seems to be gone as of 0.34.02
(0020784)
Footkerchief   
2012-02-26 21:26   
Awesome.